SUBFAMILY III. LOCUSTIN.E. 409 



waste places generally, and are seldom found in any numbers in 

 the favorite wooded and sheltered luumts of the short-winged spe- 

 cies. Being possessed of ample powers of flight they travel long 

 distances from their birth-place. At times some of them, as 

 sprctis and a flan-is, and rarely femur-rubrum and differentialis, 

 become possessed of the migratory instinct and congregating in 

 vast numbers, as do blackbirds in autumn, fly for scores or even 

 hundreds of miles, stopping wherever food appears plentiful, and 

 then moving again onward, leaving behind them a waste more 

 desolate than did the Huns in northern France. 



The number of species of long-winged forms of the genus 

 known from the eastern States is 18 as against 33 of the short- 

 winged ones, but what the former lack in number of species is 

 more than made up in individuals, for they comprise the most 

 common and therefore the most injurious of our locusts. Many 

 nominal species have in the past been described, based upon the 

 color of the hind tibiae, slight variations in the form of the male 

 cerci and furcula, length of tegmina and other minor and variable 

 characters. Five of these have been placed as varieties and a 

 number as synonyms in the pages which follow and time will 

 doubtless show that several of those retained as valid species 

 should be so reduced. For convenience of treatment the eastern 

 species of Division II are grouped into ten Series numbered con- 

 secutively with those of Division I. 



KEY TO EASTEEN SERIES OF LONG-WINGED MELANOPLUS. 



a. Apical hind margin of subgenital plate of male more or less elevated 

 and usually distinctly and narrowly notched at tip, rarely with only 

 a deep posterior subapical impression (Fig. 141, a, c); cerci short, 

 flat, nearly equally broad throughout, their length not much more 

 than twice as great as the middle breadth (PL III, i); mesosternum 

 of male with a blunt rounded tubercle in front of lobes. 



SERIES VIII, p. 412. 



act. Apical hind margin of subgenital plate never distinctly narrowly 

 notched, rarely with a broad and feeble emargination; cerci three 

 or more times as long as the middle breadth; mesosternum of male 

 without a tubercle. 



b. Cerci of male beyond the middle either subequal or tapering, the 

 apical half never distinctly spatulate or forked and but rarely 

 slightly wider than the middle. 



c. Furcula two-thirds as long as supra-anal plate, with basal halves 

 broad, flat, their inner edges attingent, the apical halves 

 strongly obliquely narrowed and divergent; hind tibiae blue; 

 tegmina immaculate or nearly so. SERIES IX, p. 416. 



cc. Furcula variable in length, but with basal halves never broader 

 than the apical ones and at the same time flattened and 

 attingent. 



